Zero-Copy Receive for Virtualized Network Devices

  • Kalman Meth
  • Joel NiderEmail author
  • Mike Rapoport
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 881)


When receiving network traffic on guest VMs (virtual machines) running on the KVM hypervisor, data is copied from hypervisor buffers to guest buffers. This copy incurs CPU and latency overhead. It seems desirable to avoid this copy, if possible, and to use guest buffers directly to receive network data. A number of challenges must be overcome in order to accomplish this zero-copy receive, and some additional overhead is incurred in setting it up. We present the technical details on a zero-copy receive design and implementation and discuss the resulting performance degradation. In our implementation, the savings in CPU from avoiding the copy is overshadowed by the extra handling required for the smaller and often underutilized buffers .


Zero-copy Virtual networking KVM 



This work is part of the OPERA project, which has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 688386 (OPERA) and 645402 (Mikelangelo).


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.IBM Research Labs - HaifaHaifaIsrael

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